The disclosure relates to threaded tubular connections and the like. More particularly, the disclosure relates to an apparatus and method for joining tubular members using threaded sections in a manner that increases the thread torque capacity.
In the oil and gas production industry, pipe or other tubular sections may be connected via threaded connections, such as mating pin and box ends. The threaded connections are often subjected to large torsion forces during downhole operations like drilling. The torque or yield strength of the connection is dictated by the thread profile, the material properties and the dimensions of the mating threaded components. However, due to space or other constraints in a well bore, often times the threaded connection design is limited as to the size and thread type that can be used, thereby limiting the yield strength of the connection. For example, a rotary shouldered connection between two tubular components may include an internal makeup shoulder disposed between the end of the pin and an internal shoulder of the box end. Connections with an internal makeup shoulder may have reduced torque capacity, and may be susceptible to fatigue crack initiation in the pin threads. Thus, it is desirable to increase the yield or torque strength of a threaded connection in other ways.
There remains a need for a threaded connection that advantageously increases the torque strength of a threaded connection, particularly while also staying within current downhole design specifications and the geometric constraints of an earthen borehole.